Models For Volatilization Characteristics Of Biomass Fast Pyrolysis In A Down-flow Tube Reactor

It's a new technique which using the temperature difference between the solid carrier and biomass particles made biomass can be quickly heated to pyrolysis temperature. Using this process principles, the down flow tube reactor was developed which heated by ceramic balls solid heat carrier was developed for biomass pyrolysis. Currently, the study on the pyrolysis mechanism of the down tube is insufficiency. Therefore, It must do in-depth study on pyrolysis rule under the high heating rate, and further grasp the pyrolysis mechanism of biomass in the down tube reactor, for providing theoretical basis for optimization and guidance of the reactor, through experiments and theoretical analysis.In this article, the experimental data of mixing flow law of biomass power and ceramic balls obtained from a simulate transparent down tube using PIV technology, with those data flow law and velocity distribution can be got as well as the total residence time of biomass is 2.018s in the rector and the average velocity of biomass is 0.793m/s in the down tube. This provide basis for the pyrolysis dynamic law of biomass in the rector.The pyrolysis experiment of corn straw and rice husk was carried out on the biomass pyrolysis device of the down flow tube reactor,and the pyrolysis temperature were 450℃,500℃,550℃,the solid carbon residue were collected at the distance of 150mm,550mm,850mm,1150mm, and Ash tracer method was used for taking advantage of biomass pyrolysis devolatilization degree. It is assumed the dynamics equation of fast pyrolysis of biomass could be described by Arrhenius kinetics model, as the formula in the down tube. The apparent frequency factor A and apparent activation energy E/R of the model were derived form experimental data, So the characteristic volatilization equation of corn stalks and rice hulls in the down tube:The apparent frequency factor and apparent activation energy values of Corn stalk and Rice hulls are different in different kinds of biomass.The experimental and theoretical curves of the model are basically the same trend by the comparison of the experimental data and the calculation of the model.